Separation Anxiety

I thought we were through with this whole separation anxiety thing. He got over it fairly early in his short little life. And then we changed classes at church. Now, I drop him off and he cries like I'm abandoning him for life, and his heart is now broken. I try to make it as least drawn out as I can. I hug, I say goodbye, I'll be back, I wave and I'm gone. Now, I have to say, at least he can now stay in class the whole service. I no longer see the dreaded number come up on the screen during service, as I try to subtly and quietly get up and leave. He's made progress. But, inevitably, when I go in to get him at the end of service, he's sobbing again, a look of betrayal in his eyes. Some of the other children's mothers have already come...where were you? And then, for a good couple of minutes, he's still crying/whimpering. Why does it take so long for him to calm down? You would think he would see me, and Bam! all good. It's like he's at the top of a roller coaster of tears and he can't stop until after he's reached the bottom of the proverbial hill. I can't really blame the kid. I'm a stay-at-home mom; this is the only time I leave him with people he doesn't know. What do I expect? Especially when I waited until he was 6 months to leave him in the nursery at all. I dug this hole of anxiety myself. Now I must lie in it.